GB2159564A - Improved pin-tumbler lock - Google Patents

Abstract

A cylinder lock which comprises a cylindrical casing 3; a rotatable cylinder 1 in the front portion of the casing; and a fixed cylinder 2 in the rear portion of the casing; wherein said rotatable cylinder and the wall of said casing having cooperative radially aligned bores 123 and 32, and radial tumbler pins 123a and drivers 123b received in said radially aligned bores, said rotatable cylinder and said fixed cylinder having co-operative longitudinally aligned bores 122 and 21, and longitudinal tumbler pins 122a and drivers 122b received in said longitudinally aligned bores, and said rotatable cylinder being released when said longitudinal tumbler pins are moved rearward simultaneously by the action of a key. <IMAGE>

Description

SPECIFICATION Improved pin-tumbler lock This invention relates to a pin-tumbler lock, particularly to a lock having a rotatable cylinder which is locked by radial tumbler pins and tumbler drivers provided in co-operative radially aligned bores of the cylinder and the casing and longitudinal tumbler pins and tumbler drivers provided in co-operative longitudinally aligned bores of the cylinder and a fixed cylinder provided in the casing.

It is known in the art that a typical pintumbler lock includes a rotatable cylinder lock which is placed in locked and unlocked positions by means of tumbler pins and drivers provided in co-operative radially aligned bores in the cylinder and in the wall of the casing and an insertable key. The releasing of the cylinder is accomplished by the action of the key only in the radial direction of the cylinder.

An object of the invention is to provide a pin-tumbler lock of improved construction in which the rotatable cylinder in the cylinder casing is released from its locked position by the key which must act in radial and longitudinal directions, thereby increasing the security rendered by the lock.

The following and other objects can be achieved in accordance with the invention through the provision of a cylinder lock which includes a cylindrical casing, a rotatable cylinder in the front portion of the casing, and a fixed cylinder in the rear portion of the casing, wherein the rotatable cylinder and the wall of the casing have co-operative radially aligned bores and radial tumbler pins and drivers received in the radially aligned bores, the rotatable cylinder and the fixed cylinder have co-operative longitudinally aligned bores and longitudinal tumbler pins and drivers received in the longitudinally aligned bores, and the rotatable cylinder is released when the radial tumbler pins are moved outward and the longitudinal tumbler pins are moved rearward simultaneously by the action of a key.

The cylinder lock may further include a core passing through the center of rotatable and fixed cylinders. The core is fixed relative to the rotatable cylinder and is movable relative to the fixed cylinder.

The rotatable cylinder has a longitudinal groove adjacent to the surface of the core and communicated with the inner terminating ends of the radially aligned bores where in the radial tumbler pins extend into the groove for being acted by the inserted key.

The longitudinal tumbler pins are angularly spaced apart at the same distances from the center of the cylinder and extend beyond the front end of the rotatable cylinder. Each of the pins has one part of its front end face abutted against the inner side of the front end of the casing and another part of its front end face for being acted by the key which is inserted.

The presently preferred exemplary embodiment will be described in detail with reference to the accompanying drawings.

Figure 1 is an exploded view of a cylinder lock and a key constructed according to the invention; Figure 2 is a perspective view of a cylinder lock and the key as the same embodiment as Fig. 1; Figure 3 is a front view of the cylinder lock of Fig. 2; Figure 4 is a sectioned view of the lock taken along the line Y-Y of Fig. 3; and Figure 5 is a sectioned view of the lock taken along the line Z-Z of Fig. 3.

Referring to the drawing, there is shown a pin-tumbler lock which includes a cylindrical casing 3 accomodating a rotatable cylinder 1 having an axial bore in which is inserted a core 11. The front end of the rotatable cylinder 1 abuts against the shoulder formation 33 of the casing, thereby forming an annular space between the front end of the rotatable cylinder and the inner side of the casing 1.

The front end 111 of the core 11 extends beyond the front end of the rotatable cylinder 1 and is exposed through a key hole 34 provided in the front end of the casing 3. The diameter of the core 11 is smaller than the diameter of the key hole 34, thereby forming an annular space around the core 11. The rear end 11 2 of the core 11 extends beyond the rear ends of the cylinder 1 and the casing 3 to be connected to a bolt or latch of a known locking mechanism (not shown).

At the upper side of the periphery of the core 11 is provided lengthwise a longitudinal groove 11 3. There is further provided a lock pin 121 in a radial bore of the cylinder 1 which has its one end engaged in the groove 113, thereby making the core 11 unmovable with respect to the rotatable cylinder 1.

The cylinder 1 is further provided with a longitudinal groove 11 4 adjacent to the iower side of the periphery of the core 11 to act as a part of the key hole. The groove 114 is communicated with five radial tumbler holes 1 23 which are in alignment with radial blind holes 32 provided in the casing 3. Each tumbler hole 1 23 and each blind hole 32 cooperatively receives a radial tumbler pin 123a, a radial tumbler driver 1 23b and a compression spring 123c. When the rotatable cylinder 1 is in its locked position, the ends of the tumbler drivers 1 23b respectively extend in part into the tumbler holes 1 23 by the force of the springs 123c.

There is further provided a fixed cylinder 2 having an axial bore and sleeved onto the rear portion of the core 11. The cylinder 2 is locked against movement by means of two lock pins 22 inserted in aligned holes provided in the casing 3 and the cylinder 2. Six longitudinal blind holes 21 are further pro vided in the cylinder 2 at regular interval in the angular direction and the same radial distances from the center of the cylinder.

These blind holes 21 are in alignment with longitudinal tumbler holes 122 provides in the rotatable cylinder 1. Each longitudinal blind hole 21 and each longitudinal tumbler hole 1 22 co-operatively receive a longitudinal tumbler pin 122a, a longitudinal tumbler driver 1 22b and a spring 122c. When the rotatable cylinder 1 is locked, the tumbler drivers 1 22b extend in part into longitudinal tumbler holes respectively by the actions of the springs 122c, and the front ends of the tumbler pins 1 22a extend beyond the front end of the cylinder 1 and have their respective parts of end faces 1 22d abut against the inner side of the front end of the casing 3, as better shown in Figs. 3 and 5.

There is further provided a key 4 used for operating the lock. The key 4 includes a webshaped handle 45, a hollow portion 41, a positioning block 43 and a rod portion 42.

The hollow portion 41 is provided with grooves 411 at its periphery and the rod portion 42 is provided with recesses 44.

When the key is inserted into the lock through the key hole 34, the rod portion 42 is received in the groove 114 of the cylinder 1 and the hollow portion 43 is received in the annular space around the core 11. To insert the key 4 in the lock in a proper position, the positioning block 43 must be just received in a rectangular groove 31 of the casing 3. The recesses 44 which are different in their depths depress the ends of the radial tumbler pins 1 23a which are protruded into the groove 11 4 in such a manner that the contact surfaces of the tumbler pins 1 23a and the tumbler drivers 1 23b are flush with the contact surfaces of the cylinder 1 and the casing 3.

The grooves 411 of the hollow portions 41 which are different in their depths in the longitudinal directions respectively depress the front ends of the longitudinal tumbler pins 1 22a in such a manner that the contact surfaces of the tumbler pins 1 22a and the tumbler drivers 1 22b are flush with the contact surfaces of the cylinders 1 and 2. At this condition, the cylinder 1 is released from its locked position together with the core 11.

With the invention thus explained, it is apparent that obvious modifications and vaiations can be made without departing from the scope of the invention. It is therefore intended that the invention be limited only as indicated in the appended claims.

Claims (5)

1. A cylinder lock comprising: a cylinderical casing; a rotatable cylinder in the front portion of the casing; and a fixed cylinder in the rear portion of the casing; wherein said rotatable cylinder and the wall of said casing having co-operative radially aligned bores, and radial tumbler pins and drivers received in said radially aligned bores, said rotatable cylinder and said fixed cylinder having co-operative longitudinally aligned bores, and longitudinal tumbler pins and drivers received in said longitudinally aligned bores, and said rotatable cylinder is released when said radial tumbler pins are outward and said longitudinal tumbler pins are moved rearward simultaneously by the action of a key.

2. A cylinder lock as claimed in Claim 1, further includes a core passing through the center of said rotatable and fixed cylinders, said core being fixed relative to said rotatable cylinder and being movable relative to said fixed cylinder.

3. A cylinder lock as claimed in Claim 2, wherein said rotatable cylinder have a longitudinal groove adjacent to the surface of said core and communicated with the inner termi-, nating ends of said radially aligned bores, and in which said radial tumbler pins extend into said groove for being acted by the inserted key.

4. A cylinder lock as claimed in Claim 3, wherein said longitudinal tumbler pins are angularly spaced apart at the same distances from the center of the cylinder and extend beyond the front end of the rotatable cylinder, each of said pins having one part of its front end face abutted against the inner side of the front end of the casing and another part of its front end face for being acted by the key which is inserted.

5. A lock as substantially described herein before with reference to the accompanying drawings.